A 36.0−g sample of an unknown metal at 99°C was placed in a constant-pressure calorimeter containing 70.0 g of water at 24.0°C. The final temperature of the system was found to be 28.4°C. Calculate the specific heat of the metal. (The heat capacity of the calorimeter is 12.4 J/°C.)

0.52849 j /g °C

Explanation:

Given the following :

Mass of metal = 36g

Δ Temperature of metal = (28.4 - 99)°C = - 70.6°C

Mass of water = 70g

Δ in temperature of water = (28.4 - 24.0) = 4.4°C

Heat lost by metal = (heat gained by water + heat gained by calorimeter)

Quantity of heat(q) = mcΔT

Where; m = mass of object ; c = specific heat capacity of object

Heat lost by metal:

- (36 × c × - 70.6) = 2541.6c - - - - (1)

Heta gained by water and calorimeter :

(70 × 4.184 × 4.4) + (12.4 × 4.4) = 1288.672 + 54.56 = 1343.232 - - - - (2)

Equating (1) and (2)

2541.6c = 1343.232

c = 1343.232 / 2541.6

c = 0.52849 j /g °C

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year